How to Register a custom SecurityTokenHandler with Code

Hi,

I've created a custom CustomUserNameSecurityTokenHandler an registered it within the configuration-file this way:

<system.identityModel><identityConfiguration><securityTokenHandlers><remove type="System.IdentityModel.Tokens.WindowsUserNameSecurityTokenHandler, System.IdentityModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/><add type="MiniSTS.CustomUserNameSecurityTokenHandler, MiniSTS"/></securityTokenHandlers></identityConfiguration></system.identityModel>

This works fine, but now I'm wondering how to do this using code. I've tried it with the following code, but it hasn't worked.

var host = CreateServiceHost();

var cred = new ServiceCredentials();

cred.UseIdentityConfiguration = true;
var idConfig = cred.IdentityConfiguration;

idConfig.SecurityTokenHandlers.Remove(idConfig.SecurityTokenHandlers.OfType<WindowsUserNameSecurityTokenHandler>().First());
idConfig.SecurityTokenHandlers.AddOrReplace(new CustomUserNameSecurityTokenHandler());

host.Description.Behaviors.Add(cred);
host.Open();

Console.WriteLine("gestartet");
Console.ReadLine();

What's the problem here?

Wishes,

Manfred